1. Field of the Invention
This invention generally relates to a one-way clutch assembly to be interposed between an inner rotating member and an outer rotating member to permit a relative rotation between the inner and outer rotating members only in one direction, and in particular to a roller-synchronized one-way clutch assembly including a plurality of rollers which are synchronized in clutching operation.
2. Description of the Prior Art
A one-way clutch assembly using a plurality of rollers is well known in the art, and typical prior art examples are shown in FIGS. 1 and 2. As shown in FIG. 1, a one-way clutch assembly is interposed between a pair of outer and inner rotating members 1 and 2, which are provided concentrically to be rotatable relative to each other, for controlling the relative rotation between these outer and inner rotating members 1 and 2. In the prior art structure shown in FIG. 1, a plurality of cam surfaces, each having a predetermined shape, are formed at the outer peripheral surface of the inner rotating member 2 in the form of a recess, and a roller 3 is disposed inside of each of the cam surfaces 2a to be movable therein, and the roller 3 is normally urged in a predetermined direction by means of a spring 4. As shown in FIG. 1, the cam surface 2a is slightly inclined with respect to the radial direction, so that the roller 3 is pushed against the cam surface 2a of the inner rotating member 2 and the inner peripheral surface of the outer rotating member 1 as being urged by the spring 4. As a result, the counterclockwise rotation of the outer rotating member 1 relative to the inner rotating member 2 is prohibited, but the clockwise rotation of the outer rotating member 1 relative to the inner rotating member 2 is allowed.
In FIG. 1, the structure enclosed by the circle A illustrates the type in which the spring 4 is received in a hole formed in the inner rotating member 2 and a cap 5 is fitted onto the forward end of the spring 4; on the other hand, the structure enclosed by the circle B illustrates the type in which use is made of an accordion type spring. In addition, the prior art one-way clutch assembly shown in FIG. 2 is similar in many respects to the prior art one-way clutch assembly shown in FIG. 1; however, in the case of FIG. 2, the cam surfaces are formed not on the inner rotating member 2 but on the outer rotating member 1. In the case of the one-way clutch assembly shown in FIG. 2, the counterclockwise rotation of the outer rotating member 1 relative to the inner rotating member 2 is permitted, but the clockwise rotation of the outer rotating member 1 relative to the inner rotating member 2 is prohibited.
The roller type one-way clutch as described above is relatively simple in structure and the relative rotation between the outer and inner rotating members 1 and 2 may be controlled. However, various components such as rollers 3 and springs 4 are separately provided and it is rather difficult to assemble. Besides, difficulties are also encountered in repair and maintenance. Moreover, when it is required to form holes in either of the outer and inner rotating members 1 and 2 as illustrated by the structure enclosed by the circle A, its processing is rather difficult, which tends to push up the cost. In addition, in the assembled condition, each of the rollers 3 is independent in operation in principle, so that the performance tends to be irregular in the circumferential direction. As a result, the overall operation tends to be unstable and lacks reliability.
The U.S. Pat. No. 3,166,169 issued to Wade et al. discloses a one-way roller clutch with plural cage means in which all of the rollers are synchronized in clutching operation. However, Wade et al. teaches to provide a plurality of springs same in number as the rollers with each spring having one end in contact with the associated roller. With this structure, difficulty will be encountered in assemblage and also the performance may differ from roller to roller. As a result, the overall operation of the clutch assembly may not be uniform in the circumferential direction.